I am reading the datasheet of the LM3409, specifically section 9 "Application and implementation". My intent is to understand how to calculate the values of the components needed for my specific application.
I aim to drive a single LED with a maximum constant current of 2.7A, from a 42V PSU, and use the analog dimming feature of the LM3409 to control the brightness (similar to the circuit in section 9.2.2).
Most of what is explained in the datasheet is sufficiently clear to me, except for how to determine the inductor ripple current (ΔiL-PP) and the LED ripple current (ΔiLED-PP).
Chapters 8.3.4 (Inductor Current Ripple) and 9.1.3 (LED Ripple Current) seem to imply that I should be choosing these values, but they give me no clear indication as to how to choose them.
Can anyone help me understand how to choose these values ?